Over 130 clients were able to access ALP without proper assessment.

The Securities and Futures Commission (SFC) has fined Citigroup Global Markets Asia Limited (CGMAL) $4m over regulatory breaches in relation to the operations of its alternative liquidity pool (ALP).

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Dark pools or ALPs, are anonymous trading platforms enabling investors to trade big blocks of shares without having news of their orders move the price.

CGMAL's ALP, Citi Match, failed to comply with relevant requireements from December 2015 to August 2016 resulting in over 130 clients accessing the ALP without being assessed if they were qualified investors.

"CGMAL also failed to provide the clients with the ALP Guidelines prior to routing their first orders to Citi Match,"the regulator said in a statement.

In a statement, the US-based bank announced that it had already taken remedial actions to correct its error. “Citi would like to confirm that there was no financial impact on affected clients, who were all qualified investors, and no client opted-out of Citi Match after being specifically provided with the ALP guidelines, which were available at all relevant times on Citi’s website.”